Stationary power tools typically employ a spindle to transfer rotational power from the motor to a cutting tool mounted directly upon the arbor of the spindle.
One spindle design characterized by superior performance with respect to rotational vibration and run out comprises a pulley surface and an arbor machined as a solid unit. However, power tools frequently require the use of differently sized arbors to facilitate the use of variously sized cutting tools and such "solid" spindles complicate the procedure and exacerbate the cost of interchanging the arbors as the entire spindle must be replaced.
A second spindle design which facilitates interchangeability of the arbors is known as a "cartridge spindle". Cartridge spindles comprise a pulley surface with a central steel shaft capable of releasably retaining variously sized arbors. While cartridge spindles simplify the interchangeability of variously sized arbors, they lack the superior performance characteristics of the solid spindle design as they inherently suffer from substantial vibration and run out. In addition, the cartridge spindle are considerably more expensive to manufacture and maintain than solid spindles.
Accordingly, a substantial need exists for an inexpensive spindle capable of providing the superior performance characteristics of a solid spindle while permitting simple and easy interchangeability of arbors.